Greater London · England
Sand mastic for sash & case windows in Agar Town, Greater London
Traditional burnt sand mastic around sash and case windows and doors in stone and brick in Agar Town, with a 12-month guarantee on every job. Ask us for a quote.
- Silicone on a period window that looks wrong
- Gaps round a timber door in stone or brick
- Mastic that needs renewing before redecorating
Sand mastic in Agar Town, done properly
Sand mastic is the traditional way to point the gap between a timber window frame and the stone or brick around it. It’s made from sand and a linseed-oil-based binder, applied by hand. On older homes, it suits the building far better than silicone. We work on brick reveals, tenement windows and timber door frames, and common reasons people get in touch are gaps where the frame meets the masonry and crumbling sand mastic round a window.
London has a lot of flats and conversions, where windows are often on upper floors. In a converted house or block, the lease normally says who is responsible for the windows, so it’s worth checking before booking, and access in Agar Town is something to talk through when you book.
Each job carries a 12-month guarantee, large or small.
- Place
- Agar Town (NW1W, NW1, N1)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Quote
- A clear price before work begins
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Keeping the joints in good condition
Aftercare is simple, and it makes a real difference:
- Leave the new mastic unpainted
- Do not run silicone over sand mastic
- Go gently near the mastic when preparing windows
- Find out about consent before window work on a listed home
Do not touch or press the mastic while it hardens. It skins over quickly but needs longer to fully harden.
An open joint round the box lets weather through. Left, the gap tends to get bigger.
How the job changes by surface
Tenement and terrace windows
In shared buildings, the windows may be part of a wider repair so it’s worth checking responsibilities.
Period and listed homes
Period homes look their best with traditional materials, and sand mastic is one of them.
Common questions in Agar Town
Can you do sand mastic in Agar Town?
Yes. Our work covers London and the South East, and Agar Town is part of that. Just call 0345 464 0079 or send us an email with a few details of the job.
Is parking an issue for sand mastic in Agar Town?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. That way the visit can be planned around it.
Can new sealant go over the old?
No. We remove every bit of old sealant first, so the new sealant bonds properly.
Does someone need to be in?
We need access to the joints, so we will agree that with you when we book. Indoors, that generally means someone at home.
Do you work for letting agents?
Yes, often. We can quote for several properties at once.
Is it worth trying it myself?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Can you do several jobs on one visit?
Yes, we can. More than one area can be quoted together.
How long does sand mastic take?
A typical job takes a few hours per window, depending on the condition of the joints, including the preparation. We will confirm how long when we quote.
Places near Agar Town
Also in Agar Town
Why deal with it now?
New mastic over crumbling mastic won’t hold. We remove the loose material first so the new mastic stays put. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and by the time it shows on a wall or ceiling in Agar Town, the repair is bigger than the sealant job would have been.
Homes and businesses are quoted the same way: the amount of work, the access and the products needed. Call for a quick quote and we’ll go through it with you.
Why us?
- Every job guaranteed for a year
- Experience in homes, commercial sites and hotels
- 4.9 on Google from 180+ five-star reviews
- Approved under the ARBOMaster scheme
Take a look at how sealant jobs are priced and what customers say.
Honest limits
In fairness, there are a few things sealant will not fix:
- Sashes that need overhauling
- Whether work needs listed building consent
- Broken panes
If in doubt, phone 0345 464 0079 or email us and we will say what we think.
What we seal
- Stone surrounds
- Brick reveals
- Timber door frames
- Sash and case windows
- Tenement windows
- Period & listed homes
Sand mastic in Agar Town: local notes
Historic houses like Winfield House (about 1.5 miles west) are a reminder that the area around Agar Town has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
As a London address, Agar Town can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Homes close to All Saints include some older properties, and frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Agar Town is about 1 mile north-west of St Pancras, in Greater London. Anywhere in NW1W, we cover sand mastic for homes and businesses. Across Greater London, we cover 764 places, Agar Town among them.
Work in NW1W, NW1 and N1 works the same way as everywhere else we cover. Sand mastic is available to properties on Water Lane, Maiden Lane and Camden Road and the roads around them. Being close to the A400 and A5200, Agar Town is easy for our applicators to reach for sand mastic. Close by, we work in Camden Town (1 mile west), Somers Town (1 mile south), Kings Cross (1 mile south-east), Kentish Town (1 mile north-west) and Barnsbury (1 mile north-east). Within a short drive, we also cover London (3 miles south-east), Kensington (4 miles south-west), Walthamstow (6 miles north-east), Whitechapel (3 miles south-east), Ruislip (12 miles west) and Brompton (3 miles south-west).
Local landmarks in Agar Town
Locally, jobs take us to homes and businesses close to Vaughan Williams Memorial Library, Golden Lion pub and North Bridge House School. Other local landmarks include Regent High School (within half a mile south) and Lewis Cubitt Park (within half a mile east). There’s a railway station in Agar Town itself: Camden Road station. Other landmarks nearby include St Pancras Hospital (less than half a mile south) and Montfichet's Tower (2.2 miles south-east). Green spaces nearby include Barnsbury Wood and St. James's Park Lake.
What happens on the day
When we arrive, we look over the joints with you first, so there are no surprises. Surfaces next to the work are protected before work begins. Most jobs take anything from a few hours to a full day, depending on how many windows. In a London area like Agar Town, the main things to plan are parking and access: let us know about parking, the floor we’ll be working on and any lift or shared entrance.
- We check the window surrounds and agree which joints need renewing.
- The loose and crumbling mastic is raked out and the joint cleaned.
- We pack any deep gaps so the mastic sits at the right depth.
- We mix the sand mastic and apply it by hand, shaping it to the joint.
- The finish is dressed so it sits neatly against the stone or brick.
Getting ready for the visit
- Mention any tricky access
- Tell us about any previous sealing or DIY attempts
- Where the joints are inside, avoid wetting them before we arrive
Ask for a quote
We don’t publish a price list, as no two jobs are quite the same. Instead, we send you a clear quote for your job. To arrange one, ring 0345 464 0079 or send us an email.
Related advice
Signs you need sand mastic in Agar Town
Age is the main cause. Sand mastic is a maintenance item like any pointing and how long it lasts depends on the weather it faces.
People generally contact us when they notice one of these:
- Draughty sash windows at the surround
- Crumbling sand mastic round a window
- Failed mastic on an exposed elevation
- Cracked mastic round a front door frame
Letting a property close to Camden Road station? Then any sash windows need sound mastic to keep draughts and rain out.
What to look for in a quote
- What product goes in the joint
- What insurance they hold
- Whether all the old sealant comes out first
- How long the guarantee is
Landlords, agents and businesses in Agar Town
Whether it’s one flat or a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a one-year guarantee.
We work for landlords and letting agents as well as homeowners. Resealing between tenancies keeps a property looking cared for.